Driving connections for airplane-engines



B. D THOMAS. DRIVIIIG CONNECTIONS FOR AIRPLANE ENGINES.

APPLICATION FILED FEB. 28, I920.

Patented Oct. 25, 1921.

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B. D. THOMAS.

DRIVING CONNECTIONS FOR AIRPLANE ENG NES.

APPLICATION FILED FEB. 28,1920.

Patented Oct. 25, 1921.

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TORNEY APPLICATION FILED FEB- 23, I920.

Patented Oct 25, 1921. 4 SHEETSSHEET 3.

M'TORNEY B. 0. THOMAS. DRIVING CONNECTIONS FOR AIRPLANE ENGINES. APPLICATION FILED FEB 28. I920.

Patented 001;. 25, 1921.

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BENJAMIN DOUGLAS THOMAS, OF I THACA, NEW YORK, ASSIGNOR 0F ONE-TENTH TO THOMAS-MORSE AIRCRAFT CORPORATION, OF ITHACA, NEW YORK, A CORPORA- TION OF NEW YORK.

DRIVING .CONNECTIONS FOR AIRPIiANE-ENGINES.

Specification of Letters Patent.

Patented Oct. 25, i921.

Application filed February 28, 1920. Serial No. 361,947.

. T0 all whom it may concern:

Be it known that I, BENJAMIN DOUGLAS,

and has for its object to provide an improved system of drivin connections between a plurality of engines and a corresponding number of propellers whereby t e efiiciency of the power is increased, and a greater degree of safety obtained.

According to, my improvement, a plurality of engine units are connected to a plurality of propellers located on a common axis and in close proximity to each other, the adjacent propellers being connected to rotate in opposite directions.

It has been found desirable to place two or more engines in an airplane, in order to increase thepower and reliability of the ma chine, but heretofore the additional engines have been placed in the wings, or one in the front and one in the rear of the center'compartment. it is very di'flicult to fly if one engine fails to function, and the additional weight at these points is also objectionable. It has also been found difficult to mount two or more engines in the center compartment, and have them operate efliciently and independently.

My improvement, however, provides practically two or more power plants, or engines, in one, but each operating wholly independently of'the other, or the others, and so arranged that if one of said engines should I fail, the others will not be interfered with,

but will continue to function, with the result that the airplane will remain in the air, with somewhat diminished power, but will be able to reach its objective and not be forced to land under unfavorable conditions.

In the accom anying drawings: Figure 1 is a plan of one ibrm of airplane power plant embodyin my improvement, and showing two six-cylinder engines mounted on a common crank case and eachdriving a propeller independently of the other; Fig. 2, an end elevation of the same; Fig. 3, a plan, similar With the engines in the wings,

to Fig. 1, but showing three six-cylinder engines driving three propellers; Fig. 4, a side elevation showing two V type engines arranged in tandem; Fig. 5, a plan showing two multi-cylinder V-shaped engines mounted on a common crank case and driving two propellers; Fig. 6, an'end elevation of the same; and Figs. 7 and 8, side and end elevations, respectively, showing two multiradial-cylinder engines arranged in tandem.

Broadly stated, my improvement comprises two or more engines, or power plants, and a corresponding number of propellers located on a common axis, each engine being connected to drive its respective propeller independently of the other.

In Figs. 1 and 2, there are shown two engines, A and B, each having six vertical cylinders arranged parallel and mounted on a common crank case, 15. The'crank shaft, 10 of engine, B, is provided with a gear wheel, 11 ,meshing with gear, 12*, on the tubular shaft, 13*, mounted in suitable bearings in the base, 15, and carrying, at its forward end, the propeller, 14'. In a similar manner, the crank shaft, 10, of the other engine, A, is provided with a gear, 11, meshing with gear, 12*, on the shaft, 13, extending through the tubular shaft, 13", and carrying the propeller, 14*, at its outer end.

The propellers are thus arranged to rotateupon substantially the same axis in close proximity to each other, and as the engines are located in reverse positions, it will be noted from the gearing that the propellers are connected to turn in opposite directions, as indicated by the arrows in Fig. 2.

Fig. 8 shows a similar construction with the addition of another engine, C, located at the rear of the other engines and having its crank shaft, 10, in the same axis with the other pro eller shafts. The crank shaft,-

' the shaft, 13

11 and '12", with the propeller shafts, 13* and 13 respectively. The tubular shaft, 13 may extend through the V shaped space between the cylinders of the engine, B, and be rotatably' mounted in the frame in any suitable manner, while the shaft, 13, is rotatably mounted within the shaft, 13*, and may also be provided at its rear end with a bearing in the frame of theengine, A. A flexible coupling, 16, may be inserted in As theengines are located back to back, and the gears of the respective engines are driven from the opposite ends of the crank shafts, the propeller shafts and the corresponding propellers, 14 and 14, will be rotated in opposite directions and entirely independently of each other.

The construction of-Figs. 5 and 6, is similar to that of Figs. 1 and 2, except that the two engines, A'and 13, instead of being of the vertical six-cylinder type, are of the V type mounted on the common crank case, l 5, the connections otherwise being substantlally the same as before described.

The modification shown in Figs. 7 and 8- is another tandem arrangement of the two engines, A and B, the same as shown in Fig. 4, except that the engines are of the radial multi-cylinder type, with fixed cylinders. The propeller. shafts, 13 and 13 are mounted in suitable bearings upon the frame between two adjacent cylinders, .as indicated, and are driven in opposite directions by the respective pairs of gears, 11 and 12, and 11 and 12", as before described.

Various other modifications as to the type of engines employed, and the form of the connections used, may be readily worked out, and aILembOdying the essential features of my invention comprising two or more engines, eachdriving a separate propeller, the propellers being mounted on a common axis, in close proximity to each other, and rotating in Opposite direction.

The tandem arrangement shown in Fig. 4 may be referred for some-reasons, since these stansard- V shaped engines may be purchased in the market, and be readily modifiedto install the propeller shafts; also any desired number of engines may be readily connected up to the corresponding number of propellers, as it is simply a matter of providing the desired number of concentric hollow shafts for the same.

.fixed on the front end of 1. In an airplane, the combination of a I plurality of engines, a hollow shaft mount- ;ed on the engine frame and having a driving gear at the rear thereof, a propeller said shaft, another shaft'rotatably mounted within and extending through said hollow shaft, another propeller fixed on the front end of the inner shaft, a driving gear atthe rear end of said inner shaft, and driving connections from the respective engines to said gears on the-outer and inner shafts.

2. In an airplane, the combination of a plurality of engines, a hollow shaft mount ed on the engine frame, a propeller fixed on the front end of sa-i'dshaft, a driving gear fixed on the rear end of said shaft, another shaft rotatably mounted within and extending through said hollow shaft, another propeller fixed on the front end of the inner shaft, a driving gear at the rear end of the inner shaft, and independent driving connections between said engines and the respective driving gears on said shafts for rotating the same in opposite directions.

3. u an airplane, the/combination of a plurality of engines arranged in tandem onthe center line, a hollow shaft mounted on the forward engine frame, a propeller fixed on said shaft in front ofsaid engine, another shaft rotatably mounted within said hollow shaft, another propeller mounted on the forward end of said inner shaft, and

"independent driving connections from said engines to the respective shafts at the rear of the forward engine.

4. In an airplane, the combination of'a plurality, of'engines arranged in tandem on the center line, a hollow shaft mounted on the forward engme frame,a propeller fixed -on said shaft in front of said engine, another shaftrotatably mounted within said hollow shaft, another propeller mounted on the forward end of said inner shaft, driving gears on said'shafts atthe rear of the forward engine, and independent driving connec-- 

